Effects of genotype and growing locations on properties of wheat starch gels

This study examines the contributions of genotype and the effects of growing location and storage to variability in the strength, syneresis and in vitro enzyme digestibility of wheat (Triticum aestivum L.) starch gels. The study involved starch that was extracted from five wheat varieties grown in four locations. Length of storage at 4 °C after hydrothermal treatment of the starch accounted for 30–50% of the variance in the three gel properties. Genotype contributed significantly to variability in syneresis and enzyme digestibility of the starch gels, indicating a degree of heritability of these characteristics in the wheat varieties studied. Gel strength was strongly influenced by effects from the growing location. Syneresis and enzyme‐resistant starch were negatively correlated with granule size and swelling power of native starch. Syneresis was also correlated negatively with pasting viscosities of starch granules, and positively with amylose content and pasting temperature. Gel strength was correlated positively with relative crystallinity and negatively with the breakdown of peak viscosity. Length of storage had a major influence on gel strength, syneresis and in vitro enzyme digestibility, although genotype contributed significantly to variability in syneresis and enzyme‐digestibility. Growing conditions were a significant influence on gel strength.